Complementary Metal-Oxide Semiconductor (CMOS) technology is commonly used to manufacture integrated circuits (ICs). Examples of modern ICs include microprocessors, microcontrollers, memories, etc. In various implementations, one or more components within an IC may operate based upon one or more “voltage references.” To provide these voltage references, one or more “reference circuits” may be designed within the IC.
An example of a reference circuit is the “bandgap circuit.” A bandgap circuit is configured to output a temperature independent voltage reference with a value of approximately 1.25 V, or another value suitably close to the theoretical 1.22 eV bandgap of silicon at 0 K—that is, the energy required to promote an electron from its valence band to its conduction band to become a mobile charge. For example, a bandgap circuit may include a set of Self-Cascade MOS Field-Effect Transistor (SCM) structures and one or more bipolar transistor(s) operating in an open loop configuration.
Also, in some cases, a reference circuit may employ a startup circuit or the like. Generally speaking, a startup circuit is configured to ensure that the reference circuit is operating in desired or known states.